Lined up across the stage was the classic fado backing trio of Portuguese guitar, acoustic guitar and acoustic bass guitar, and in the darkness came the distinctive and declamatory voice of the singer who has done the most to bring Portugal's traditional answer to the blues to a new, global audience. Mariza has been away for nearly two years, taking time off, she explained, to have a baby and get married; dressed tonight in a long black gown, she managed to look even thinner and taller than before.

There was no new material in this set, which began with songs from her last album Fado Tradicional, from 2011, and included material from four previous albums. But there were, however, changes in her style and presentation. Her closest international rival, Ana Moura, has been popularising fusions of fado and western pop, and Mariza introduced a drummer for several songs; there was even a decidedly non-fado drum solo towards the end. On a more positive note, she had calmed and varied her performance. Her last London appearance was marred by constant full-tilt intensity, but here there were passages where she sounded far more relaxed, as on Meu Fado Meu. Much of her set consisted of traditional fado, in which new lyrics are added to traditional melodies, but she included a startling demonstration of musical fado, in which songs of all kinds are treated with the emotional intensity of great fado. The encores included an unexpectedly effective fado version of the Nat King Cole weepie Smile, sung in English.

It was a good night, too, for Scottish singer-songwriter Alasdair Roberts, who opened with a gently compelling solo set matching jaunty finger-picking guitar work with bleak lyrics on The Merry Wake and other songs from his latest album.

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